1. Field of the Invention
The present invention relates to a new process for the synthesis of the known antitumor antibiotics 4'-epidaunorubicin, 3',4'-diepidaunorubicin and their doxorubicin analogs. The invention also relates to certain novel intermediates used in the process.
2. The Prior Art
U.S. Pat. No. 4,039,663 discloses 4'-epidaunorubicin and its use in treating certain mammalian tumors. U.S. Pat. No. 4,058,519 similarly discloses 4'-epidoxorubicin and its use. Finally, U.S. Pat. No. 4,112,076 discloses in like manner 3',4'-diepidaunorubicin and 3',4'-diepidoxorubicin.
The starting material for the process of the invention is N-trifluoroacetyl daunorubicin, a known material whose preparation from daunorubicin (also known) is described in U.S. Pat. No. 3,803,124.